Single implant sacroiliac joint fusion system using a posterior approach for minimal tissue disruption

ABSTRACT

A method for preparing a sacroiliac joint for stabilization which may include approaching a posterior aspect of the sacroiliac joint inferior to a PSIS with a defect-creating tool assembly, creating a defect in the sacrum and the ilium defined by at least one noncircular cross-sectional shape, delivering an implant having a body with a length extending between proximal and distal ends, the body including at least one cylindrical body with a longitudinal axis and an opening at the proximal end aligned with the longitudinal axis of the cylindrical body, a pattern of openings spaced along the cylindrical body and a planar member coupled with and extending along the cylindrical body. The implant may be implanted with the length generally following a plane of the sacroiliac joint such that it is advanced from a generally posterior to anterior approach while the body of the implant bridges the joint.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/992,987 filed May 30, 2018, which application is acontinuation of U.S. patent application Ser. No. 15/910,753 filed Mar.2, 2018, which application is a continuation of U.S. patent applicationSer. No. 15/828,677 filed Dec. 1, 2017, now U.S. Pat. No. 9,931,212,which application is a continuation of U.S. patent application Ser. No.15/061,524 filed Mar. 4, 2016, now U.S. Pat. No. 9,833,320, whichapplication is a divisional of U.S. patent application Ser. No.13/946,790 filed Jull 19, 2013, now U.S. Pat. No. 9,333,090, whichapplication claims priority to and incorporates by reference in itsentirety U.S. Provisional Patent Application Nos.; 61/674,277, filedJul. 20, 2012; 61/800,120, filed Mar. 15, 2013; and 61/674,130, filedJul. 20, 2012.

Application Ser. No. 13/946,790 is also a continuation-in-partapplication of U.S. patent application Ser. No. 13/475,695 (“the '695application”), which was filed May 18, 2012, now U.S. Pat. No.9,381,045. The '695 application is a continuation-in-part application ofand claims priority to U.S. patent application Ser. No. 13/236,411 (“the'411 application) filed Sep. 19, 2011, now U.S. Pat. No. 9,017,407.

The '411 application is a continuation-in-part application of and claimspriority to U.S. patent application Ser. No. 12/998,712 (“the '712application”), which was filed May 23, 2011, now U.S. Pat. No.8,979,928. The '712 application is the National Stage of InternationalPatent Cooperation Treaty Patent Application PCT/US2011/000070 (the “PCTapplication”), which was filed Jan. 13, 2011. The PCT application claimspriority to U.S. Provisional Patent Application 61/335,947, which wasfiled Jan. 13, 2010.

The present application is also a continuation-in-part application ofU.S. patent application Ser. No. 14/344,876, filed Mar. 13, 2014, whichapplication is a National Stage of Patent Cooperation Treaty (PCT)Application No. PCT/US2012/055892, filed Sep. 18, 2012, whichapplication is a continuation-in-part application of U.S. patentapplication Ser. No. 13/475,695 filed May 18, 2012, now U.S. Pat. No.9,381,045, which application is a continuation-in-part application ofU.S. patent application Ser. No. 13/236,411 (“the '411 application),filed Sep. 19, 2011, now U.S. Pat. No. 9,017,407.

The '411 application is a continuation-in-part application of and claimspriority to U.S. patent application Ser. No. 12/998,712 (“the '712application”), which was filed May 23, 2011, now U.S. Pat. No.8,979,928. The '712 application is the National Stage of InternationalPatent Cooperation Treaty Patent Application PCT/US2011/000070 (the “PCTapplication”), which was filed Jan. 13, 2011. The PCT application claimspriority to U.S. Provisional Patent Application 61/335,947, which wasfiled Jan. 13, 2010.

All of the aforementioned applications are hereby incorporated byreference in their entireties into the present application.

The delivery approaches and methodologies disclosed in the above-listedapplications and incorporated herein are applicable to the implants anddelivery tools disclosed in the present application.

FIELD OF THE INVENTION

A sacroiliac joint fusion system that provides a method of fixation andfusion of the sacroiliac joint and sacroiliac fixation fusion implantwhich upon placement facilitates stability and fusion of the sacroiliacjoint.

BACKGROUND

The sacroiliac joint is the joint between the sacrum and the ilium ofthe pelvis, which are joined by ligaments. In humans, the sacrumsupports the spine and is supported in turn by an ilium on each side.The sacroiliac joint is a synovial joint with articular cartilage andirregular elevations and depressions that produce interlocking of thetwo bones.

Pain associated with the sacroiliac joint can be caused by traumaticfracture dislocation of the pelvis, degenerative arthritis, sacroiliitisan inflammation or degenerative condition of the sacroiliac joint,osteitis condensans ilii, or other degenerative conditions of thesacroiliac joint. Currently, sacroiliac joint fusion is most commonlyadvocated as a surgical treatment for these conditions. Fusion of thesacroiliac joint can be accomplished by several different conventionalmethods encompassing an anterior approach, a posterior approach, and alateral approach with or without percutaneous screw or other typeimplant fixation. However, while each of these methods have beenutilized for fixation and fusion of the sacroiliac joint over the pastseveral decades, substantial problems with respect to the fixation andfusion of the sacroiliac joint remain unresolved.

A significant problem with certain conventional methods for fixation andfusion of the sacroiliac joint including the anterior approach orposterior approach may be that the surgeon has to make a substantialincision in the skin and tissues for direct access to the sacroiliacjoint involved. These invasive approaches allow the sacroiliac joint tobe seen and touched directly by the surgeon. Often referred to as an“open surgery”, these procedures have the attendant disadvantages ofrequiring general anesthesia and can involve increased operative time,hospitalization, pain, and recovery time due to the extensive softtissue damage resulting from the open surgery. A danger to open surgeryusing the anterior approach can be damage to the L5 nerve root whichlies approximately two centimeters medial to the sacroiliac joint.Additionally, these procedures typically involve fixation of thesacroiliac joint (immobilization of the articular surfaces of thesacroiliac joint in relation to one another) by placement of one or morescrews or by placement of one or more trans-sacroiliac implants (asshown for example by the non-limiting example of FIG. 1) or by placementof implants into the S1 pedicle and iliac bone. Use of trans-sacroiliacand S1 pedicle-iliac bone implants can also involve the risk of damageto the lumbosacral neurovascular elements. Damage to the lumbosacralneurovascular elements as well as delayed union or non-union of thesacroiliac joint by use of these procedures may require revision surgeryto remove all or a portion of the implants or repeat surgery as to thesecomplications.

Another significant problem with conventional procedures utilizingminimally invasive small opening procedures can be that the proceduresare technically difficult requiring biplanar fluoroscopy of thearticular surfaces of the sacroiliac joint and extensive surgicaltraining and experience. Despite the level of surgical training andexperience, there is a substantial incidence of damage to thelumbosacral neurovascular elements. Additionally, sacral anomalies canfurther lead to mal-placement of implants leading to damage ofsurrounding structures. Additionally, these procedures are oftenperformed without fusion of the sacroiliac joint which does not removethe degenerative joint surface and thereby does not address thedegenerative condition of the sacroiliac joint which may lead tocontinued or recurrent sacroiliac joint pain.

Another significant problem with conventional procedures can be theutilization of multiple trans-sacroiliac elongate implants, which do notinclude a threaded surface. This approach requires the creation oftrans-sacroiliac bores in the pelvis and nearby sacral foramen which canbe of relatively large dimension and which are subsequently broachedwith instruments which can result in bone being impacted into the pelvisand neuroforamen. The creation of the trans-sacroiliac bores andsubsequent broaching of the bores requires a guide pin which may beinadvertently advanced into the pelvis or sacral foramen resulting indamage to other structures. Additionally, producing the trans-sacroiliacbores, broaching, or placement of the elongate implants may result indamage to the lumbosacral neurovascular elements, as above discussed.Additionally, there may be no actual fusion of the articular portion ofthe sacroiliac joint which may result in continued or recurrent painrequiring additional surgery.

Another substantial problem with conventional procedures can be thatplacement of posterior intra-articular distracting fusion implants andbone grafts as described for example by U.S. patent application Ser. No.10/797,481 of Stark, now U.S. Pat. No. 7,648,509, may be inadequate withrespect to removal of the articular surface or cortical bone, theimplant structure and fixation of the sacroiliac joint. The method maynot remove sufficient amounts of the articular surfaces or corticalsurfaces of the sacroiliac joint to relieve pain in the sacroiliacjoint. The implant structures described may have insufficient engagementwith the articular surfaces or cortical bone of the sacroiliac joint foradequate fixation or fusion. The failure to sufficiently stabilize andfuse the sacroiliac joint with the implant structures and methodsdescribed by the Stark application may result in a failure to relievethe condition of sacroiliac joint being treated.

The inventive sacroiliac fusion system described herein addresses theproblems associated with conventional methods and apparatuses used infixation and fusion of the sacroiliac joint.

SUMMARY OF THE INVENTION

Accordingly, a broad object of the invention can be to provide aninventive fixation fusion implant for fixation and fusion of thesacroiliac joint. Embodiments of the fixation fusion implant can providea first pair of radial members which extend in generally opposedrelation a distance radially outward from the longitudinal axis of agenerally linear elongate body and as to certain embodiments can furtherprovide a second pair of radial members which extend in generallyopposed relation a distance radially outward from the longitudinal axisof the generally linear elongate body and can be in substantiallyperpendicular relation to the first pair of radial members.

Another broad object of the invention can be to provide an inventivemethod for fixation and fusion of the sacroiliac joint which utilizesthe inventive fixation fusion implant. The inventive method comprisesthe steps of performing a minimally invasive posterior surgery thatallows access to the posterior lateral aspect of the sacroiliac jointfor removing a sufficient portion of the cartilage and subchondral boneto relieve the condition for which the sacroiliac joint is being treatedand to configure a portion of the sacroiliac joint to provide an implantreceiving space in the plane of the sacroiliac joint(non-trans-sacroiliac) configured to allow interference fitting of thefirst pair radial members of the fixation fusion implant between theopposed surfaces of the implant receiving space, and thereby locatingthe first one of the second pair of radial members in the bone of thesacrum and the second one of the second pair of radial members in thebone of the ilium. The inventive method avoids conventionaltrans-sacroiliac placement of S1 pedicle or intrailiac screws whileproviding immediate fixation of the sacroiliac joint.

Another broad object of the invention can be to provide one or more boneingrowth aperture elements which communicate between the opposedsurfaces of the first pair of radial members or through the generallylinear elongate body each having a configuration which allows the boneof the sacrum and ilium to grow through the implant to facilitate fusionof the sacrum to the ilium and fixation of the sacroiliac joint.

Another broad object of the invention can be to provide particularembodiments of the inventive fixation fusion implant with an amount ofcurvature along the length of the implant which allows placement ofembodiments of the fixation fusion implant which have an increasedsurface area which remain within the articular portion of the sacroiliacjoint.

Naturally, further objects of the invention are disclosed throughoutother areas of the specification, drawings, photographs, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an anterior view of the pelvic region and a conventionalmethod and device for stabilizing the sacroiliac joint.

FIG. 2 is a perspective view of a particular embodiment of the fixationfusion implant.

FIG. 3 is a first side view of a particular embodiment of the fixationfusion implant.

FIG. 4 is a first implant end view of a particular embodiment of thefixation fusion implant.

FIG. 5 is a second implant end view of a particular embodiment of thefixation fusion implant.

FIG. 6 is second side view of the particular embodiment of the fixationfusion implant shown in FIG. 3 rotated about 90 degrees about thelongitudinal axis.

FIG. 7 is a first side view of another particular embodiment of thefixation fusion implant having a coat material which facilitatesosseointegration of the fixation fusion implant with the bone.

FIG. 8 is a cross section 8-8 as shown in FIG. 7 of that particularembodiment of the fixation fusion implant.

FIG. 9 is a perspective view of an embodiment of the fixation fusionimplant having an amount of curvature along the longitudinal axis.

FIG. 10 is a first side view of the particular embodiment of thefixation fusion implant shown in FIG. 9.

FIG. 11 is a first implant end view of a particular embodiment of thefixation fusion implant shown in FIG. 9.

FIG. 12 is a second implant end view of a particular embodiment of thefixation fusion implant shown in FIG. 9.

FIG. 13 is second side view of the particular embodiment of the fixationfusion implant shown in FIG. 10 rotated about 90 degrees about thelongitudinal axis.

FIG. 14 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including insertion of a needle into the articularplane of the sacroiliac joint to inject a radiographic dye to allowfluoroscopic visualization of the sacroiliac joint.

FIG. 15 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including fixing the tubular needle within thesacroiliac joint as a guide wire.

FIG. 16 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including advancing a body of a cannulated probe alongthe needle fixed in the sacroiliac joint to fixed location at theanterior portion of the sacroiliac joint.

FIG. 17 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including advancing a tissue dialator along the body ofthe cannulated probe fixed in the sacroiliac joint to allow placement ofa access tube against the surface of the sacrum and ilium to expose thesacroiliac joint.

FIG. 18 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including replacement of the tissue dialator with afirst drill jig which receives a cannulated drill for production of afirst bore hole substantially along the articular plane of thesacroiliac joint.

FIG. 19 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including replacement of the first drill jig with asecond drill jig which allows additional bore holes to be produced inrelation to the first bore hole each substantially along the articularplane of the sacroiliac joint.

FIG. 20 is a cross section view through the sacroiliac joint whichillustrates a method of implanting an embodiment of the fixation fusionimplant the step including replacement of the second drill jig (or thefirst drill jig depending on the method) with a broach jig whichreceives a cannulated broach which can be advanced into the sacroiliacjoint to produce an implant receiving space.

FIG. 21A provides a cutaway view of the sacroiliac joint showingplacement of a particular embodiment of the fixation fusion implant inthe implant receiving space produced by the method illustrated in FIGS.14-20.

FIG. 21B is an enlarged view of a portion of FIG. 21A showing placementof a particular embodiment of the fixation fusion implant in the implantreceiving space produced by the method illustrated in FIGS. 14-20.

FIG. 21C is a cross section view 9C-9C shown in FIG. 21B which shows theconfiguration of the implant receiving space produced by the methodillustrated in FIGS. 14-20 and a particular embodiment of the fixationfusion implant implanted therein implanted.

FIG. 22 provides a side view of the ilium with the articular surfaces ofthe sacroiliac joint and an embodiment of the fixation fusion implantlocated within the articular plane of the sacroiliac joint shown inbroken line.

FIG. 23 provides a side view of the ilium with the articular surfaces ofthe sacroiliac joint and an embodiment of the fixation fusion implantlocated substantially within the articular plane and to a limited extentextra-articular of the sacroiliac joint shown in broken line.

FIG. 24 provides a side view of the ilium with the articular surfaces ofthe sacroiliac joint and another embodiment of the fixation fusionimplant located within the articular plane of the sacroiliac joint shownin broken line.

FIG. 25 is a perspective view of a particular embodiment of the fixationfusion implant having an amount of curvature along the longitudinal axisand further broken into implantable segments.

FIG. 26 provides a side view of the ilium with the articular surfaces ofthe sacroiliac joint and the embodiment of the fixation fusion implantshown in FIG. 25 located within the articular plane of the sacroiliacjoint shown in broken line.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Generally, a sacroiliac joint fusion system that provides a method offixation and fusion of the sacroiliac joint and a fixation fusionimplant which upon placement within the sacroiliac joint facilitatesstability and fusion of the sacroiliac joint.

Now referring primarily to FIG. 1, which shows one commonly utilizedconventional method and device for fixation of the sacroiliac joint (1).The conventional device shown comprises one or more substantially linearelongate members (2) which can be inserted into correspondinglydimensioned trans-iliac bores (3) with a first portion extending in thebone of sacrum (4) and a second portion extending into the bone of theilium (5) thereby extending cross the sacroiliac joint (1). The one ormore substantially linear elongate members (2) (which can be configuredas cylindrical rods which can further include an amount of taper orfurther include a spiral thread coupled to the exterior surface to avoidthe need for generating trans-iliac bores) in trans-iliac placement canlocate the ilium (5) in fixed relation to the sacrum (4). However, thistrans-iliac placement of such substantially linear elongate members (2)can have the disadvantages above described.

Now referring primarily to FIG. 2 and also FIGS. 3-6, an embodiment ofan inventive fixation fusion implant (6) is shown which in part includesan elongate body (7) which defines a longitudinal axis (8). The elongatebody (7) has a configuration of sufficient dimension to avoiddeformation under the normal forces of surgical placement and fixationof the ilium (5) in relation to the sacrum (4). Accordingly, while theembodiment of the fixation fusion implant (6) shown in FIG. 2 can begenerally cylindrical or circular in cross section; the invention is notso limited, and the elongate body (7) can have any of a numerous andvaried configurations consistent with the method herein after describedsuch as oval, triangular, rectangular, square, diamond, or the like. Asone non-limiting example, the generally cylindrical elongate body (7)shown in FIG. 2 can depending on the application have a diameter of inthe range of about 0.5 centimeters (“cm”) to about 1 cm and a lengthdisposed between a first end and a second end in the range of about 3 cmand about 6 cm.

As to particular embodiments of the invention, the elongate body (7) canfurther include an axial bore (9) that bounds an axial pathway (10)which communicates between a first implant end (11) and a second implantend (12) of the elongate body (7). The axial bore (9) allows forplacement within the axial pathway (10) a guide wire (13) (or otherguide member) on which embodiments of the fixation fusion implant (6)can be guided for insertion into the sacroiliac joint (1)(furtherdescribed below).

Again referring primarily to FIG. 2 and FIGS. 3-6, embodiments of thefixation fusion implant (6) can further include a first radial member(14) and a second radial member (15) each coupled to the externalsurface of the elongate body (7) generally in line with the longitudinalaxis (8) and substantially the entire length of the elongate body (7).Each of the first radial member (14) and the second radial member (15)can extend radially outward from the elongate body (7) substantially inopposed relation (180 degrees apart about the elongate body (7));however, the invention is not so limited, and as to certain embodiments,the first radial member (14) and the second radial member (15) can bespaced about the elongate body (7) a greater or lesser number ofdegrees. While the configuration of each of the first radial member (14)or second radial member (15) can vary as necessary to provide acorrespondingly variable amount of surface area engageable within theplane of the articular surfaces (16) of the sacrum (4) and ilium (5)sufficient for fixation of the sacroiliac joint (1) upon implantation,each the first radial member (14) and the second radial member (15)(andadditional radial members) can each include a pair of opposed faces(17)(18) disposed a thickness (19a) apart and having an area bound by atop edge (20), a pair of side edges (21)(22) and a bottom edge (23). Thefirst of the pair of side edges (21) can be connected as above describedto the elongate body (7) locating the second side edge (22) a distanceoutward from the longitudinal axis (8) of the elongate body (7). As anon-limiting example, each of the first radial member (14) and thesecond radial member (15) can be substantially rectangular inconfiguration having a height (28 a) between the first of the pair ofside edges (21) and the second of the pair of side edges (22) in therange of about 0.2 cm and about 1 cm. Understandably, a lesser diameterelongate body (7) may include a first radial member (14) and a secondradial member (15)(or other radial members) having greater height (28 a)and a greater diameter elongate body (7) may require a first radialmember (14) and a second radial member (15)(or other radial members)having lesser height (28 a).

The top edge (20) of each of the first radial member (14) and the secondradial member (15) can terminate substantially in alignment with thefirst implant end (11) of the elongate body (7). The bottom edge (23) ofthe first radial member (14) and the second radial member (15) canterminate substantially in alignment with second implant end (12) of theelongate body (7). As to certain embodiments, the bottom edge (23) canfurther include an angle element (24) which angles outward from theelongate body (7) commencing at the second implant end (12) and joiningthe second of pair of side edges (22) a distance toward the firstimplant end (11). The angle element (24) can have a degree angle (25)from perpendicular with the longitudinal axis (8) in a range of aboutfifteen degrees to about thirty degrees, as shown in FIG. 2.

Again referring primarily to FIG. 2 and FIGS. 3-6, certain embodimentsof the fixation fusion implant (6) can further include a third radialmember (26) and as to certain embodiments a fourth radial member (27)each coupled to the external surface of the elongate body (7) at alocation which allows upon implantation at least a portion of the thirdradial member (26) to locate in the bone of the sacrum (4) or the ilium(5) and the fourth radial member (27) to locate in the bone of thesacrum (4) or the ilium (5). As to the non-limiting embodiment of thefixation fusion implant (6) shown in FIG. 3, the third radial member(26) and the fourth radial member (27) can be connected generally inline with the longitudinal axis (8) of the elongate body (7). Each ofthe third radial member (26) and the fourth radial member (27) canextend radially outward from the elongate body (7) substantially inopposed relation (about 180 degrees apart) and in perpendicular relation(about 90 degrees) to the first radial member (14) and the second radialmember (15)(see also FIGS. 8 and 9; however, the invention is not solimited, and the third radial member (26) and the fourth radial member(27)(if the embodiment includes a fourth radial member (27)) can bespaced about the elongate body (7) in relation to each other and inrelation to the first radial member (14) and the second radial member(15) a greater or lesser number of degrees depending on the applicationand the amount of desired engagement with the bone of the sacrum (4) orilium (5).

The configuration of each of the third radial member (26) or the fourthradial member (27) can vary as necessary to provide an amount of surfacearea engageable with the bone of the sacrum (4) and ilium (5) sufficientfor facilitating fixation of the sacroiliac joint (1) upon implantationand to further provide a resistance to rotation or other undesiredmovement of the fixation fusion implant (6) at the implant location inthe sacroiliac joint (1). Accordingly, embodiments of the fixationfusion implant (6) having a third radial member (26) and the fourthradial member (27) can provide a pair of opposed faces (17)(18) disposeda thickness (19 b) apart and have an area bound by a top edge (20), apair of side edges (21) (22) and a bottom edge (23) in similarconfiguration as above described for the first radial member (14) andthe second radial member (15). The first of the pair of side edges (21)can be connected as above described to the elongate body (7) locatingthe second side edge (22) a distance outward from the longitudinal axis(8) of the elongate body (7). As a non-limiting example, each of thethird radial member (26) and the fourth radial member (27) can have asubstantially rectangular configuration having a height (28 b) betweenthe first of the pair of side edges (21) and the second of the pair ofside edges (22) in the range of about 0.1 cm and about 0.4 cm. The topedge (20) of each of the third radial member (26) and the fourth radialmember (27) can terminate substantially in alignment with the firstimplant end (11) of the elongate body (7). The bottom edge (23) of thethird radial member (26) and the fourth radial member (27) can terminatesubstantially in alignment with second implant end (12) of the elongatebody (7). As to certain embodiments, the bottom edge (23) of the thirdradial member (26) and the fourth radial member (27) can further includethe angle element (24) which angles the second of the pair of side edges(22) toward the first implant end (11) of the elongate body (7). Theangle element (24) can have a degree angle (25) from perpendicular withthe longitudinal axis (8) in a range of about fifteen degrees to aboutthirty degrees; however, the invention is not so limited and withrespect to certain embodiments of the invention there may be no angleelement (24) or the angle element may be greater or less than within therange of about fifteen degrees to about thirty degrees. Additionally,the angle element (24) can be similar as shown in the figures or can bedissimilar between the radial members of a particular fixation fusionimplant (6) depending on the application.

Again referring primarily to FIG. 2 and FIGS. 3-6, and withoutlimitation to forgoing, the third radial member (26) and the fourthradial member (27) can have a lesser height (28 b) than the first radialmember (14) and second radial member (15) because while the structure ofthe third radial member (26) and the fourth radial member (27) appearsimilar to the first radial member (14) and the second radial member(15), the function is substantially different. The first radial member(14) and the second radial member (15) have a configuration (height,length, thickness, surface area, and location on the external surface ofthe elongate body, as above described) capable of or allowinginterference fit within an implant receiving space (29) surgicallyproduced in the articular plane (30) of the sacroiliac joint (1), asfurther described below, and capable of fixation of the sacroiliac joint(1) upon placement within the implant receiving space (29), and whichcan further allow for incorporation by bony ingrowth about and throughthe fixation fusion implant (6) or osseointegration with the externalsurface of the fixation fusion implant (6)(or both) resulting in fusionof the sacroiliac joint (1). By contrast, the third radial member (26)and as to those embodiments having a fourth radial member (27) have aconfiguration (height, length, thickness, surface area, and location onthe external surface of the elongate body, as above described) capableof being forcibly urged a depth into the cancellous bone of the sacrum(75) or cancellous bone of the ilium (76) as the implant receiving space(29) receives the fixation fusion implant (6) to an extent sufficient tofurther resist rotation of the fixation fusion implant (6) subsequent toplacement in the implant receiving space (29) and boney fusion of thecancellous bone to the fixation fusion implant (6).

Again referring primarily to FIG. 2 and FIGS. 3-6, particularembodiments of the fixation fusion implant (6) can further include oneor more aperture elements (31) which communicate between the opposedfaces (17)(18) of the first radial member (14) or the second radialmember (15) or both. The amount of open space of an aperture element(31) can be defined by an aperture perimeter (32) which can be ofnumerous and varied configurations of sufficient dimension to allow thesurfaces of the ilium (5) or sacrum (4)(or both) adjacent to the firstradial member (14) or the second radial member (15)(or both) of thefixation fusion implant (6) placed within the implant receiving space(29) to grow a distance into the aperture element (31) or through theaperture element (31) or fuse within the aperture element (31). As anon-limiting example, the aperture perimeter (32) can be of generallyoval configuration resulting in an oval aperture element (31) located inthe first radial member (14) or the second radial member (15)(orboth)(or located in additional radial members depending upon theembodiment) with the length of the oval aperture element (31) alignedwith the length of the first radial member (14) or second radial member(15) and being about one quarter to about two thirds the length of theradial member and having a width of the oval aperture element (31)located between the sides (21)(22) of the first radial member (14) orsecond radial member (15) and being about one quarter to about twothirds the height (28 a). Additionally, the elongate body (7) canfurther include aperture elements (31) which communicate between theexternal surfaces between the radial members (14)(15)(26)(27).

Again referring primarily to FIG. 2 and FIGS. 3-6, embodiments of thefixation fusion implant (6) can further include an anti-migrationelement (33) coupled to the first implant end (11) of the elongate body(7). The anti-migration element (33) can take the form of an enlargedterminal portion of the first end of the elongate body (7), an increasein the height (28) of one or more of the radial members (such as flaringoutward) proximate the first implant end (11) of the elongate body (7).As one non-limiting example, the anti-migration element (33) can takethe form of an end cap (34) having a generally circular configurationwith the center substantially aligned with the longitudinal axis (8) ofthe elongate member 0 and extending radially outward sufficient distanceto prevent advancement of the second implant end (12) of the fixationfusion implant (6) further into the sacroiliac joint (1) subsequent toimplantation in the implant receiving space (29). While the end cap (34)shown is generally circular in configuration, the end cap (34) can haveend cap perimeter (35) which defines an oval, square, rectangle, orother configuration useful in fixing the location of the fixation fusionimplant (6) in relation the sacroiliac joint (1). Additionally, theanti-migration element (33) can have sufficient dimensions to furtherinclude one or more bores (36) which communicate between the opposedsurfaces (37)(38) of the anti-migration element (33) and dimensioned toreceive mechanical fasteners (39)(such threaded members, barbed members,locking members or the like) which can be driven or rotated to engage aportion of the mechanical fastener with the sacrum (4) or the ilium (5).

The elongate body (7) along with the other elements of the fixationfusion implant (6) above described can be fabricated or formed from aplurality of pieces or as a single piece of biocompatible material or acombination of biocompatible and biodegradable materials of suitablydimensioned particles, sheets, or other constructional forms or formableor moldable materials suitably bound or formed or molded to provideconfigurations in accordance with the invention.

Now referring primarily to FIGS. 7 and 8, embodiments of the fixationfusion implant (6) can further include a coat (40) coupled to orgenerated on all or a part of the external surface of the fixationfusion implant (6). The coat (40) can be of any composition that can becoupled to the fixation fusion implant (6) capable of biocompatibleosseointegration with the bone of the ilium (5) and sacrum (4), such aspure alumina, titanium-dioxide, hydroxyapatite, calcium triphosphate, orthe like. As a non-limiting example, the coat (40) can be applied byplasma spraying with a plasma torch, plasmatron or a plasma gun.Alternately, the coat (40) can be achieved by producing a surfaceroughness, porosity, or irregularity of the fixation fusion implant (6)by sand blasting, bead blasting, molding, or the like. The coat (40) canhave a thickness in the range of about 40 gm and about 100 gm. Again,embodiments of the fixation fusion implant (6) can be configured as amaterial having interconnecting pores throughout such as TRABECULARMETAL available from Zimmer, P.O. Box 708, 1800 West Center Street,Warsaw, Ind. 46581-0708 or a metallic foam such as a titanium foamavailable from the National Research Council Canada, 1200 Montreal Road,Bldg. M-58, Ottawa, Ontario, Canada.

Again referring primarily to FIG. 2 and FIGS. 3-6, embodiments of theinvention can further include one or more biologically active agent(s)(41) which can be applied directly to the external surface of thefixation fusion implant (6) or can be mixed with a biocompatiblematerial or biocompatible biodegradable material which can be applied tothe external surface of the fixation fusion implant (6) or otherwisemade a part of the fixation fusion implant (6). As to particularembodiments of the fixation fusion implant (6), the biologically activeagent(s)(41) can be mixed with an amount of a biocompatiblebiodegradable material (71) and located within one or more of theaperture elements (31).

“Biocompatible” for the purposes of this invention means the ability ofany material to perform the intended function of an embodiment of theinvention without eliciting any undesirable local or systemic effects onthe recipient and can include non-biodegradable materials such as:ceramic; metals or steels such as titanium alloys or rigid polymericmaterials or rigid laminate materials or composites which includesuitably dimensioned particles of metals or steels dispersed withinrigid laminate materials, or suitably sized particles of biocompatiblematerials suitably bound or formed to provide configurations,polyurethanes, polyisobutylene, ethylene-alpha-olefin copolymers,acrylic polymers and copolymers, vinyl halide polymers and copolymers,polyvinyl esters, polyvinylidene chloride, polyacrylonitrile, polyvinylketones, polyvinyl aromatics such as polystyrene, copolymers of vinylmonomers and olefins such as ethylene-methyl methacrylate copolymers,acrylonitrile-styrene copolymers, ABS resins, ethylene-vinyl acetatecopolymers, polyamides such as Nylon 66 and polycaprolactone, alkydresins, polycarbonates, polyoxyethylenes, polyimides, polyesters, epoxyresins, rayon-triacetate, cellophane, polyether ether ketone (PEEK),bone-from-wood available from the Istituto di Scienza e Tecnologia deiMareriali Ceramici, Faenza, Italy, or the like, or biodegradablematerials, as herein described.

“Biodegradable” for the purposes of this invention means the ability ofany biocompatible material to breakdown within the physiologicalenvironment of the sacroiliac joint by one or more physical, chemical,or cellular processes at a rate consistent with providing treatment of acondition of the sacroiliac joint at a therapeutic level controllable byselection of a polymer or mixture of polymers (also referred to aspolymeric materials), including, but not limited to: polylactidepolymers (PLA), copolymers of lactic and glycolic acids (PLGA),polylactic acid-polyethylene oxide copolymers,poly(c-caprolactone-co-L-lactic acid (PCL-LA), glycine/PLA copolymers,PLA copolymers involving polyethylene oxides (PEO), acetylated polyvinylalcohol (PVA)/polycaprolactone copolymers,hydroxybutyrate-hydroxyvalerate copolymers, polyesters such as, but notlimited to, aspartic acid and different aliphatic diols, poly(alkylenetartrates) and their copolymers with polyurethanes, polyglutamates withvarious ester contents and with chemically or enzymatically degradablebonds, other biodegradable nonpeptidic polyamides, amino acid polymers,polyanhydride drug carriers such as, but not limited to, poly(sebacicacid) (PSA), aliphatic-aromatic homopolymers, andpoly(anhydride-co-imides), poly(phosphoesters) by matrix or pendantdelivery systems, poly(phosphazenes), poly(iminocarbonate), crosslinkedpoly(ortho ester), hydroxylated polyester-urethanes, or the like.

“Biologically active agents” for the purposes of this invention meansthose agents or mixture of agents which can be varied in kind or amountto provide a therapeutic level effective to mediate the formation orhealing of bone, cartilage, tendon, or to reduce, inhibit, or prevent asymptom of a condition of the sacroiliac joint subsequent to placementof an embodiment of the fixation fusion implant within the sacroiliacjoint (1) such as infection or pain and without limitation can includeagents that influence the growth of bone, alleografts, bone formingprotein, bone morphogenetic protein 2, analgesics, anesthetics,anti-inflammatory agents, antibacterials, antivirals, antifungals,antiprotozoals, anti-infectives, antibiotics such as aminoglycosidessuch as gentamicin, kanamycin, neomycin, and vancomycin; amphenicolssuch as chloramphenicol; cephalosporins, such as cefazolin HCl;penicillins such as ampicillin, penicillin, carbenicillin, oxycillin,methicillin; lincosamides such as lincomycin; polypeptide antibioticssuch as polymixin and bacitracin; tetracyclines such as tetracycline,minocycline, and doxycycline; quinolones such as ciprofloxacin,moxifloxacin, gatifloxacin, and levofloxacin; anti-viral drugs such asacyclovir, gancyclovir, vidarabine, azidothymidine, dideoxyinosine,dideoxycytosine; analgesics, such as codeine, morphine, ketorolac,naproxen, an anesthetic, lidocaine; cannabinoids; antifungal agents suchas amphotericin; anti-angiogenesis compounds such as anecortave acetate;retinoids such as tazarotene, steroidal anti-inflammatory agents such as21-acetoxypregnenolone, alclometasone, algestone, amcinonide,beclomethasone, betamethasone, budesonide, chloroprednisone, clobetasol,clobetasone, clocortolone, cloprednol, corticosterone, cortisone,cortivazol, deflazacort, desonide, desoximetasone, dexamethasone,diflorasone, diflucortolone, difluprednate, enoxolone, fluazacort,flucloronide, flumethasone, flunisolide, fluocinolone acetonide,fluocinonide, fluocortin butyl, fluocortolone, fluorometholone,fluperolone acetate, fluprednidene acetate, fluprednisolone,flurandrenolide, fluticasone propionate, formocortal, halcinonide,halobetasol propionate, halometasone, halopredone acetate,hydrocortamate, hydrocortisone, loteprednol etabonate, mazipredone,medrysone, meprednisone, methylprednisolone, mometasone furoate,paramethasone, prednicarbate, prednisolone, prednisolone25-diethylamino-acetate, prednisolone sodium phosphate, prednisone,prednival, prednylidene, rimexolone, tixocortol, triamcinolone,triamcinolone acetonide, triamcinolone benetonide, triamcinolonehexacetonide; and any of their derivatives.

As to particular embodiments of the inventive fixation fusion implant(6) the biologically active agent(s)(41) can be dispersed throughout abiocompatible or biocompatible biodegradable material (or mixture ofbiocompatible materials or mixture of biocompatible biodegradablematerials) by mixing biologically active agent(s)(41) into the meltedbiocompatible or biodegradable polymer and then solidifying theresulting material by cooling, having the biologically activeagent(s)(41) substantially uniformly dispersed throughout. Thebiodegradable material or biocompatible material or mixture thereof canbe selected to have a melting point that is below the temperature atwhich the biologically active agent(s)(41) becomes reactive or degrades.Alternatively, the biologically active agent(s)(41) can be dispersedthroughout the biocompatible or biodegradable material by solventcasting, in which the biocompatible or biodegradable material isdissolved in a solvent, and the biologically active agent(s)(41)dissolved or dispersed in the solution. The solvent is then evaporated,leaving the biologically active agent(s)(41) in the matrix of thebiocompatible or biodegradable material. Solvent casting requires thatthe biocompatible or biodegradable material be soluble in organicsolvents. Alternatively, the fixation fusion implant (6) can be placedin a solvent having a concentration of the biologically activeagent(s)(41) dissolved and in which the fixation fusion implant (6) orthe biocompatible or biocompatible biodegradable material located in theaperture elements, or applied to the external surface, swells. Swellingof the fixation fusion implant (6) or portions thereof draws in anamount of the biologically active agent(s) (41). The solvent can then beevaporated leaving the biologically active agent(s)(41) within thebiocompatible or biocompatible biodegradable material. As to each methodof dispersing the biologically active agent(s) (41) throughout thebiocompatible or biodegradable biocompatible material of or coupled tothe fixation fusion implant (6), therapeutic levels of biologicallyactive agent(s)( ) can be included in biocompatible biodegradablematerial to provide therapeutically effective levels of the biologicallyactive agent to the sacroiliac joint (1) to treat a particularsacroiliac joint condition.

Other non-active agents (42) may be included in the biocompatiblebiodegradable material for a variety of purposes. For example, bufferingagents and preservatives may be employed. Preservatives which may beused include, but are not limited to, sodium bisulfite, sodiumbisulfate, sodium thiosulfate, benzalkonium chloride, chlorobutanol,thimerosal, phenylmercuric acetate, phenylmercuric nitrate,methylparaben, polyvinyl alcohol and phenylethyl alcohol. Examples ofbuffering agents that may be employed include, but are not limited to,sodium carbonate, sodium borate, sodium phosphate, sodium acetate,sodium bicarbonate, and the like, as approved by the FDA or otherappropriate agencies in the United States or foreign countries, for thedesired route of administration. Electrolytes such as sodium chlorideand potassium chloride may also be included in the formulation.

A non-limiting example, embodiments of the fixation fusion implant (6)having a biocompatible biodegradable portion with biologically activeagent(s)(41) for treating the sacroiliac joint (1) can be made bydispersing a biologically active agent(s)(41) in a biocompatiblebiodegradable material as above described to provide biologically activeagent(s) (41) release characteristics at a therapeutic level. Uponimplantation of the fixation fusion implant (6) in the sacroiliac joint(1) as described below, the biocompatible biodegradable portion of thefixation fusion implant (6) can substantially continuously releasebiologically active agent (41) to provide a localized amount of bonemorphogenetic protein 2 at therapeutic levels of about 1 milligram toabout 4 milligrams to facilitate bone regrowth. It is to be understoodthat this specific example of providing an embodiment of the fixationfusion implant (6) which delivers an amount of bone morphogeneticprotein 2 to facilitate bone regrowth, is not intended to be limiting,and embodiments of the fixation fusion implant (6) can be utilized todeliver numerous and varied active agent(s)(41) individually or incombination to treat a wide range of conditions of the sacroiliac joint(1) subsequent to implantation of embodiments of the fixation fusionimplant (6).

Now referring primarily to FIGS. 9-13 and 25, particular embodiments ofthe invention can further include an amount of curvature (43) betweenthe first implant end (11) and the second implant end (12) of thefixation fusion implant (6). The amount of curvature (43) can vary fromembodiment to embodiment of the fixation fusion implant (6) depending onthe application between a substantially linear elongate body (7) asabove described to including an amount of curvature (43) which defines aradius within a range of about 2 cm and about 6 cm.

Now referring primarily to FIG. 25, certain embodiments of the inventionhaving an amount of curvature can be provided in a plurality of implantsegments (72)(73)(74) which can be individually implanted within thearticular plane (44) as shown in FIG. 26 by the method below described.

Now referring primarily to FIGS. 14-20, a non-limiting method ofproducing the implant receiving space (29) configured to receive variousembodiments of the inventive fixation fusion device (6) within thearticular plane (44) of the sacroiliac joint (1) (as shown within brokenline of FIGS. 22, and 26) or in part within the articular plane (44) andin part the extra-articular plane (45) of the sacroiliac joint (1) (asshown by FIG. 23) is illustrated.

Now referring primarily to FIG. 14, an embodiment of the method caninclude the step of placing a patient under sedation prone on atranslucent operating table (or other suitable surface). The sacroiliacjoint can be locally anesthetized to allow for injecting a radiographicdye (46) (such as Isoview 300 radiographic contrast, or the like) underfluoroscopic guidance into the inferior aspect of the sacroiliac joint(1) to outline the lateral articular surface of the sacroiliac joint(1). Injection of the radiographic dye (46) within the sacroiliac joint(1) can be accomplished utilizing a tubular needle (47) having firstneedle end (48) which can be advanced into the sacroiliac joint (1) andhaving a second needle end (49) which removably couples to a hub (50).The hub (50) can be further configured to removably couple to a syringebarrel (51)(or other device for delivery of radiographic contrast). Inthe example of a syringe barrel (51), the syringe barrel (51) can havean internal volume capable of receiving an amount of the radiographicdye (46) sufficient for outlining the lateral articular surface of thesacroiliac joint (1). A plunger (52) can be slidingly received withinthe barrel (51) to deliver the radiographic dye (46) through the tubularneedle (47) into the sacroiliac joint (1). The tubular needle (47) canhave a gauge in the range of between about 16 gauge and about 20 gaugeand can further be incrementally marked on the external surface to allowdetermination of the depth at which the first needle end (48) hasadvanced within the sacroiliac joint (1). As the first needle end (48)advances into the sacroiliac joint (1) the radiographic dye (46) can bedelivered from within the syringe barrel (51) into the sacroiliac joint(1) to allow visualization of the sacroiliac joint (1) and location ofthe tubular needle (47) within the sacroiliac joint (1).

Now referring primarily to FIG. 15, once the first needle end (48) hasbeen sufficiently advanced into the sacroiliac joint (1) and the lateralarticular surface of the sacroiliac joint (1) has been sufficientlyvisualized, the hub (50) can be removed from the tubular needle (47)leaving the tubular needle (47) fixed within the sacroiliac joint (1) asa initial guide for the tools subsequently used in removal ofdegenerative portions of the sacroiliac joint (1) and for production ofthe implant receiving space (29). Alternately, a guide wire (13) can beinserted along substantially the same path of the tubular needle (47)for fixed engagement within the sacroiliac joint (1) and used insubsequent steps as a guide.

Again referring primarily to FIGS. 16, a small incision can be made inthe skin at the posterior superior (or as to certain embodimentsinferior) aspect of the sacroiliac joint (1), extending proximal anddistal to the tubular needle (47) along the line of the sacroiliac joint(1). A cannulated probe (53) can be slidingly engaged with the tubularneedle (47)(or guide wire (13)) extending outwardly from the sacroiliacjoint (1) (while the sacroiliac joint may be shown in the figures asbeing substantially linear for illustrative purposes, it is to beunderstood that the normal irregular features of the sacroiliac jointhave not been removed). The cannulated probe (53) can have a probe body(54) of generally cylindrical shape terminating in a spatulate tip (55)at the end advanced into the sacroiliac joint (1). A removablecannulated probe handle (56) couples to the opposed end of the probebody (54). The spatulate tip (55) can be guided along the tubular needle(47)(or guide wire (13) into the posterior portion of the articularsacroiliac joint (1) and advanced to the anterior portion of thesacroiliac joint (1) under lateral fluoroscopic visualization. Thecannulated probe handle (56) can then be removed providing the generallycylindrical probe body (54) extending outwardly from the sacroiliacjoint (1) through the incision made in the skin.

Now referring primarily to FIG. 17, an access tube (57) having insertedwithin a soft tissue dilator (58) having a blunt end (59) can beadvanced over the probe body (54) until the blunt end (59) of the softtissue dialator (58) and the corresponding end of the access tube (57)contact the posterior aspect of the sacroiliac joint (1). The softtissue dialator (58) can be removed from within the access tube (57).The external surface of the access tube (57) sufficiently engaged withthe surrounding tissue to avoid having the tissue locate with in thehollow inside of the access tube (57).

Now referring to FIG. 18, a first drill jig (60) can be advanced overthe probe and received within the access tube (57). The probe body(54)(or guide wire (13)) extending outwardly from the sacroiliac joint(1) passes through a drill guide hole (61) of the first drill jig (60).A cannulated drill bit (62) can be advanced over the probe body (54) andwithin the drill guide hole (61) of the first drill jig (60). Thecannulated drill bit (62) can be advanced into the sacroiliac joint (1)under fluoroscopic guidance to produce a first bore (63)(shown in brokenline) within the sacroiliac joint (1) to a determined depth to remove acorresponding amount of cartilage from within the sacroiliac joint (1).

Now referring to FIG. 19, as to certain embodiments of the invention,the first drill jig (60) can be removed from within the access tube (57)and a second drill jig (64) can be advanced over the probe body (54) andreceived within the access tube (57); however, the invention is notlimited to any particular number of drill jigs and as to certainembodiments of the method the first drill jig (60) can include all therequired drill guide hole(s) (61)(65) and as to other embodiments of themethod a plurality of drill jigs can be utilized in serial order toprovide all the drill guide holes (61)(65). As the particular embodimentof the invention shown by the Figures, the second drill jig (64) canprovide one or more additional drill guide holes (65) which locate inrelation to the first bore (63) to allow a second or more cannulateddrills (62) to be inserted within and advanced into the sacroiliac joint(1) to produce a second bore (66)(generally shown in broken line as63/65) or a plurality of bores within the sacroiliac joint (1) spacedapart in predetermined pattern to allow removal of sufficient cartilagefrom the sacroiliac joint (1) for placement of embodiments of thefixation fusion implant (6).

Now referring primarily to FIG. 20, in a subsequent step, the last inthe serial presentation of drill jigs is removed from within the accesstube (57) and a broach jig (67) can be advanced over the probe body (54)to locate within the access tube (57). The broach jig (67) can include abroach guide hole (68) which receives a first broach end (69) of acannulated broach (70) advanced over the probe body (54). The firstbroach end (69) can have a configuration which can be advanced into thesacroiliac joint (1) to remove a further amount of cartilage from thesacroiliac joint (1). The cannulated broach (70) can remove cartilagefrom within the sacroiliac joint (1) sufficient to produce a suitableimplant receiving space (29) configured as above described to receiveembodiments of the fixation fusion implant (6).

Now referring primarily to FIGS. 21A, 21B, and 21C, the implantreceiving space (29) can have a final configuration which allows atleast a portion of the external surface of the first radial member (14)and the second radial member (15) to engage a portion of the corticalbone (74) of the ilium (5) and at least a portion of the externalsurface of the first radial member (14) and the second radial member(15) to engage a portion of the cortical bone (73) of the sacrum (4). Asto those embodiments of the fixation fusion implant (6) which have athird radial member (26) and a fourth radial member (27), impact of thefixation fusion implant (6) into the implant receiving space (29)forcibly urges the radial members (26)(27) into the cancellous bone(75)(76) of the sacrum (4) and the ilium (5) respectively. Mechanicalfasteners (39)(such as treaded members) can be inserted through thebores (36) in the anti-migration element (33) and into the sacrum (4)and ilium (5) to fix location of the fixation fusion implant (6) withinthe implant receiving space (29).

EXAMPLE 1

An embodiment of the inventive fixation fusion implant having aconfiguration substantially as shown by FIGS. 3-6 and as above-describedwas inserted by methods as substantially above described into a patientunder direct visualization and with assisted lateral fluoroscopy. Theprocedure was performed for the purpose of assessing in an actualreduction to practice the ability of the inventive fixation fusionimplant to be safely implanted into the inferior portion of thesacroiliac joint substantially and to confirm the that implantation ofthe fixation fusion device into a implant receiving space configuredsubstantially as above-described acts to immobilize the sacroiliacjoint. The fixation fusion implant as above-described implanted into theinferior portion of the sacroiliac joint proved to immediatelyimmobilize the sacroiliac joint. The embodiment of the fixation fusiondevice was then removed and the joint was fused with a conventional openfusion technique. The implantation method and implantation of theembodiment of the fixation fusion implant was documented by fluoroscopicimaging.

As can be easily understood from the foregoing, the basic concepts ofthe present invention may be embodied in a variety of ways. Theinvention involves numerous and varied embodiments of sacroiliac jointfusion system which includes fixation fusion implants and methods ofimplanting the fixation fusion implants to provide fixation and fusionof the sacroiliac joint.

As such, the particular embodiments or elements of the inventiondisclosed by the description or shown in the figures or tablesaccompanying this application are not intended to be limiting, butrather exemplary of the numerous and varied embodiments genericallyencompassed by the invention or equivalents encompassed with respect toany particular element thereof In addition, the specific description ofa single embodiment or element of the invention may not explicitlydescribe all embodiments or elements possible; many alternatives areimplicitly disclosed by the description and figures.

It should be understood that each element of an apparatus or each stepof a method may be described by an apparatus term or method term. Suchterms can be substituted where desired to make explicit the implicitlybroad coverage to which this invention is entitled. As but one example,it should be understood that all steps of a method may be disclosed asan action, a means for taking that action, or as an element which causesthat action. Similarly, each element of an apparatus may be disclosed asthe physical element or the action which that physical elementfacilitates. As but one example, the disclosure of “an implant” shouldbe understood to encompass disclosure of the act of “implanting”—whetherexplicitly discussed or not—and, conversely, were there effectivelydisclosure of the act of “implanting”, such a disclosure should beunderstood to encompass disclosure of “an implant” and even a “means forimplanting a member.” Such alternative terms for each element or stepare to be understood to be explicitly included in the description.

In addition, as to each term used it should be understood that unlessits utilization in this application is inconsistent with suchinterpretation, common dictionary definitions should be understood to beincluded in the description for each term as contained in the RandomHouse Webster's Unabridged Dictionary, second edition, each definitionhereby incorporated by reference.

For the purposes of the present invention, ranges may be expressedherein as from “about” one particular value to “about” anotherparticular value. When such a range is expressed, another embodimentincludes from the one particular value to the other particular value.

Similarly, when values are expressed as approximations, by use of theantecedent “about,” it will be understood that the particular valueforms another embodiment. It will be further understood that theendpoints of each of the ranges are significant both in relation to theother endpoint, and independently of the other endpoint. Moreover, theterm “about” means as to any numeric value a deviation about thatnumeric value of up to ten percent.

Moreover, for the purposes of the present invention, the term “a” or“an” entity refers to one or more of that entity; for example, “amember” or “an elongate member” refers to one or more member(s) or atleast one member. As such, the terms “a” or “an”, “one or more” and “atleast one” can be used interchangeably herein.

Thus, the applicant(s) should be understood to claim at least: i) afixation fusion implant as herein disclosed and described, ii) therelated methods disclosed and described, iii) similar, equivalent, andeven implicit variations of each of these devices and methods, iv) thosealternative embodiments which accomplish each of the functions shown,disclosed, or described, v) those alternative designs and methods whichaccomplish each of the functions shown as are implicit to accomplishthat which is disclosed and described, vi) each feature, component, andstep shown as separate and independent inventions, vii) the applicationsenhanced by the various systems or components disclosed, viii) theresulting products produced by such systems or components, ix) methodsand apparatuses substantially as described hereinbefore and withreference to any of the accompanying examples, x) the variouscombinations and permutations of each of the previous elementsdisclosed.

The background section of this patent application provides a statementof the field of endeavor to which the invention pertains. This sectionmay also incorporate or contain paraphrasing of certain United Statespatents, patent applications, publications, or subject matter of theclaimed invention useful in relating information, problems, or concernsabout the state of technology to which the invention is drawn toward. Itis not intended that any United States patent, patent application,publication, statement or other information cited or incorporated hereinbe interpreted, construed or deemed to be admitted as prior art withrespect to the invention.

The claims set forth in this specification, if any, are herebyincorporated by reference as part of this description of the invention,and the applicant expressly reserves the right to use all of or aportion of such incorporated content of such claims as additionaldescription to support any of or all of the claims or any element orcomponent thereof, and the applicant further expressly reserves theright to move any portion of or all of the incorporated content of suchclaims or any element or component thereof from the description into theclaims or vice-versa as necessary to define the matter for whichprotection is sought by this application or by any subsequentapplication or continuation, division, or continuation-in-partapplication thereof, or to obtain any benefit of, reduction in feespursuant to, or to comply with the patent laws, rules, or regulations ofany country or treaty, and such content incorporated by reference shallsurvive during the entire pendency of this application including anysubsequent continuation, division, or continuation-in-part applicationthereof or any reissue or extension thereon.

The claims set forth in this specification, if any, are further intendedto describe the metes and bounds of a limited number of the preferredembodiments of the invention and are not to be construed as the broadestembodiment of the invention or a complete listing of embodiments of theinvention that may be claimed. The applicant does not waive any right todevelop further claims based upon the description set forth above as apart of any continuation, division, or continuation-in-part, or similarapplication.

1. A method for preparing a sacroiliac joint for stabilization, thesacroiliac joint defined between a sacrum and an ilium, the iliumcomprising a posterior superior iliac spine (PSIS) and a posteriorinferior iliac spine (PITS), the sacroiliac joint comprising anarticular plane defined by an articular boundary, and an extra-articularplane outside the articular boundary, the articular boundary defining ananterior boundary segment at an anterior portion of the articular plane,and a posterior boundary segment at a posterior portion of the articularplane, the articular boundary comprising a superior-posterior corner andan inferior-posterior corner at the posterior portion, the methodcomprising: approaching a posterior aspect of the sacroiliac joint witha defect-creating tool assembly comprising a drill bit and a jigcomprising first and second drill guide holes configured to guide thedrill bit along first and second trajectories, respectively; creating adefect in the sacrum and the ilium by delivering the drill bit into thesacrum and the ilium via guidance by the first and second drill guideholes of the jig, the defect having a shape defined by at least onenoncircular cross-sectional shape in a plane generally perpendicular toa joint plane of the sacroiliac joint; and delivering an implant intothe sacroiliac joint, the implant comprising a first portion of anexterior surface configured to generally match the at least onenoncircular cross-sectional shape of the defect created by thedefect-creating tool assembly.
 2. The method of claim 1, wherein thenoncircular cross sectional shape in the plane generally perpendicularto the joint plane of the sacroiliac joint comprises a rectangular shapethat bridges across the sacroiliac joint and into the sacrum and theilium.
 3. The method of claim 1, wherein the first portion of theexterior surface of the implant is defined on a first member of theimplant that is generally planar.
 4. The method of claim 3, wherein theimplant further comprises a second member having a second portion of theexterior surface of the implant, the second member comprising a sacralend and an iliac end opposite each other, the sacral end of the secondmember protruding from a sacral side of the first member, the iliac endof the second member protruding from an iliac side of the first member.5. The method of claim 4, wherein the first member is positionedcentrally between the sacral end and iliac end of the second member. 6.The method of claim 4, wherein the second member is generally planar andoriented generally perpendicular to the first member.
 7. The method ofclaim 1, wherein the implant further comprises an elongate body having agenerally cylindrical cross-sectional shape that is transverse to alength of the implant, the elongate body coupled to the first memberalong at least a portion of the length.
 8. The method of claim 7,wherein the elongate body is coupled to the first member at a midpointthereof such that the first member protrudes from opposite sides of theelongate body.
 9. The method of claim 1, wherein creating the defect inthe sacrum and the ilium is performed via fluoroscopic guidance.
 10. Themethod of claim 1, wherein the defect-creating tool assembly comprises aplurality of jigs comprising the jig and another jig, and whereincreating the defect in the sacrum and ilium comprises using the anotherjig from the plurality of jigs to guide a cutting tool selected from thedrill bit and an instrument having a chisel tip.
 11. The method of claim10, wherein the jig comprises the first drill hole in a first location,and the another jig comprises a second cutting tool hole in a secondlocation that is different than the first location.
 12. The method ofclaim 1, wherein, in delivering the implant into the sacroiliac joint,the implant passes through an access region defined between the PSIS andPIIS.
 13. The method of claim 1, wherein, in delivering the implant intothe sacroiliac joint, the implant passes through an access regiondefined between the superior-posterior corner and the inferior-posteriorcorner at the posterior portion of the articular boundary.
 14. A methodfor preparing a sacroiliac joint for stabilization, the sacroiliac jointdefined between a sacrum and an ilium, the ilium comprising a posteriorsuperior iliac spine (PSIS) and a posterior inferior iliac spine (PITS),the sacroiliac joint comprising an articular plane defined by anarticular boundary, and an extra-articular plane outside the articularboundary, the articular boundary defining an anterior boundary segmentat an anterior portion of the articular plane, and a posterior boundarysegment at a posterior portion of the articular plane, the articularboundary comprising a superior-posterior corner and aninferior-posterior corner at the posterior portion, the methodcomprising: approaching a posterior aspect of the sacroiliac joint witha defect-creating tool assembly comprising a cutting tool, the cuttingtool having a distal end and proximal end opposite thereof and an axisextending therebetween; aligning the axis of the cutting tool generallyparallel with a plane of the sacroiliac joint; creating a defect at thesacroiliac joint via the cutting tool contacting at least one of thesacrum, the ilium, and the sacroiliac joint with the axis of the cuttingtool generally parallel with the plane of the sacroiliac joint, thedefect having a shape defined by at least one noncircularcross-sectional shape in a plane generally perpendicular to the jointplane of the sacroiliac joint; and delivering an implant into thesacroiliac joint such that a first portion of an exterior surface of theimplant is at least partially received within the defect, the firstportion of the exterior surface of the implant having a cross-sectionalshape that generally matches the at least one noncircularcross-sectional shape of the defect, the implant further comprising asecond portion of the exterior surface that extends outward from thefirst portion and into the sacrum and the ilium, respectively, beyondthe defect generally matching the first portion of the exterior surfaceof the implant.
 15. The method of claim 14, wherein the second portionis connected to the first portion and has a cross-sectional geometrywhich is different from the cross-sectional geometry of the firstportion.
 16. The method of claim 14, wherein, when the first portion ofthe exterior surface of the implant is at least partially receivedwithin the defect, the second portion bridges across the sacroiliacjoint.
 17. The method of claim 14, wherein, when the first portion ofthe exterior surface of the implant is at least partially receivedwithin the defect, the second portion extends transversely to the jointplane of the sacroiliac joint.
 18. The method of claim 14, wherein thedefect-creating tool assembly further comprises a broach, and whereincreating the defect further comprises contacting the at least one of thesacrum, the ilium, and the sacroiliac joint with a distal end of thebroach.
 19. The method of claim 14, wherein the cutting tool comprises adrill.
 20. The method of claim 19, wherein the defect-creating toolassembly further comprises a drill jig configured to guide advancementof the drill, and wherein the drill jig is used to align the axis of thecutting tool generally parallel with a plane of the sacroiliac joint.21. The method of claim 14, wherein, in delivering the implant into thesacroiliac joint, the implant passes through an access region definedbetween the PSIS and PIIS.
 22. The method of claim 14, wherein, indelivering the implant into the sacroiliac joint, the implant passesthrough an access region defined between the superior-posterior cornerand the inferior-posterior corner at the posterior portion of thearticular boundary.
 23. A method for preparing a sacroiliac joint forstabilization, the sacroiliac joint defined between a sacrum and anilium, the ilium comprising a posterior superior iliac spine (PSIS) anda posterior inferior iliac spine (PITS), the sacroiliac joint comprisingan articular plane defined by an articular boundary, and anextra-articular plane outside the articular boundary, the articularboundary defining an anterior boundary segment at an anterior portion ofthe articular plane, and a posterior boundary segment at a posteriorportion of the articular plane, the articular boundary comprising asuperior-posterior corner and an inferior-posterior corner at theposterior portion, the method comprising: approaching a posterior aspectof the sacroiliac joint with a defect-creating tool assembly comprisinga drill bit, and first and second jigs, the first jig comprising a firstdrill guide hole configured to guide the drill bit along a firsttrajectory, the second jig comprising a second drill guide holeconfigured to guide the drill bit along a second trajectory that isdifferent than the first traj ectory; creating a defect in the sacrumand the ilium by delivering the drill bit into the sacrum and the iliumvia guidance by the first and second drill guide holes of the first andsecond jigs, respectively, the defect having a shape defined by at leastone noncircular cross-sectional shape in a plane generally perpendicularto a joint plane of the sacroiliac joint; and delivering an implant intothe sacroiliac joint, the implant comprising a first portion of anexterior surface configured to generally match the at least onenoncircular cross-sectional shape of the defect created by thedefect-creating tool assembly.
 24. The method of claim 23, wherein thenoncircular cross sectional shape in the plane generally perpendicularto the joint plane of the sacroiliac joint comprises a rectangular shapethat bridges across the sacroiliac joint and into the sacrum and theilium.
 25. The method of claim 23, wherein the first portion of theexterior surface of the implant is defined on a first member of theimplant that is generally planar.
 26. The method of claim 25, whereinthe implant further comprises a second member having a second portion ofthe exterior surface of the implant, the second member comprising asacral end and an iliac end opposite each other, the sacral end of thesecond member protruding from a sacral side of the first member, theiliac end of the second member protruding from an iliac side of thefirst member.
 27. The method of claim 26, wherein the first member ispositioned centrally between the sacral end and iliac end of the secondmember.
 28. The method of claim 26, wherein the second member isgenerally planar and oriented generally perpendicular to the firstmember.
 29. The method of claim 23, wherein the implant furthercomprises an elongate body having a generally cylindricalcross-sectional shape that is transverse to a length of the implant, theelongate body coupled to the first member along at least a portion ofthe length.
 30. The method of claim 29, wherein the elongate body iscoupled to the first member at a midpoint thereof such that the firstmember protrudes from opposite sides of the elongate body.
 31. Themethod of claim 23, wherein creating the defect in the sacrum and theilium is performed via fluoroscopic guidance.
 32. The method of claim23, wherein, in delivering the implant into the sacroiliac joint, theimplant passes through an access region defined between the PSIS andPIIS.
 33. The method of claim 23, wherein, in delivering the implantinto the sacroiliac joint, the implant passes through an access regiondefined between the superior-posterior corner and the inferior-posteriorcorner at the posterior portion of the articular boundary.
 34. A methodfor preparing a sacroiliac joint for stabilization, the sacroiliac jointdefined between a sacrum and an ilium, the ilium comprising a posteriorsuperior iliac spine (PSIS) and a posterior inferior iliac spine (PITS),the sacroiliac joint comprising an articular plane defined by anarticular boundary, and an extra-articular plane outside the articularboundary, the articular boundary defining an anterior boundary segmentat an anterior portion of the articular plane, and a posterior boundarysegment at a posterior portion of the articular plane, the articularboundary comprising a superior-posterior corner and aninferior-posterior corner at the posterior portion, the methodcomprising: approaching a posterior aspect of the sacroiliac joint witha defect-creating tool assembly comprising a first cutting tool, asecond cutting tool, and first and second cutting guides, the firstcutting guide comprising a first cutting guide path configured to guidethe first cutting tool along a first trajectory, the second cuttingguide comprising a second cutting guide path configured to guide thesecond cutting tool along a second trajectory that is different than thefirst trajectory; creating a defect in the sacrum and the ilium bydelivering the first cutting tool and second cutting tool into at leastone of the sacrum, the ilium, and sacroiliac joint via guidance by thefirst and second cutting guide holes of the first and second cuttingguides, respectively; and delivering an implant into the sacroiliacjoint, the implant comprising a first portion of an exterior surfaceconfigured to generally match the cross-sectional shape of the defectcreated by the defect-creating tool assembly.
 35. The method of claim34, wherein the defect defines a non-circular cross-sectional shape in aplane generally perpendicular to a joint plane of the sacroiliac joint,and wherein the first portion of the exterior surface of the implant isnon-circular.
 36. The method of claim 34, wherein the first cutting toolis a drill bit and second cutting tool is a broach.
 37. The method ofclaim 34, wherein, in implanting the implant into the sacroiliac jointvia the posterior aspect, the implant passes through an access regiondefined between the superior-posterior corner and the inferior-posteriorcorner.
 38. A method for preparing a sacroiliac joint for stabilization,the sacroiliac joint defined between a sacrum and an ilium, the methodcomprising: approaching a posterior aspect of the sacroiliac joint witha defect-creating tool assembly comprising a first cutting tool, asecond cutting tool, and first and second cutting guides, the firstcutting guide comprising a first cutting guide path configured to guidethe first cutting tool along a first trajectory, the second cuttingguide comprising a second cutting guide path configured to guide thesecond cutting tool; creating a defect in the sacrum and the ilium bydelivering the first cutting tool and second cutting tool into at leastone of the sacrum, the ilium, and sacroiliac joint via guidance by thefirst and second cutting guide paths of the first and second cuttingguides, respectively, the defect having a shape defined by across-sectional shape in a plane generally perpendicular to a jointplane of the sacroiliac joint; and delivering an implant into thesacroiliac joint, the implant comprising a body extending a lengthbetween a proximal end and a distal end, and comprising a longitudinalaxis, a first, second, third and fourth members extending along thelength generally outwardly from the longitudinal axis, and separated byone another by a first, second, third and fourth angles, the body of theimplant further comprising a first portion of an exterior surfaceconfigured to generally match the cross-sectional shape of the defectcreated by the defect-creating tool assembly.
 39. The method of claim38, wherein the first, second, third and fourth members are generallyplanar members.
 40. The method of claim 38, wherein the first, second,third and fourth angles are generally each about 90 degrees.
 41. Themethod of claim 38, wherein each pair of the first and third members,and the second and fourth members are mirror images of each other, andare arranged in a mirrored position relative to the longitudinal axis.42. The method of claim 38, wherein the implant comprises a voidpositioned in alignment with the longitudinal axis between the distalend and the proximal end, the void sized and configured such that thevoid intersects each of the first, second, third, and fourth membersresulting in the first, second, third and fourth members bridging thevoid and wherein the first, second, third, and fourth members areconnected to each other only at distal and proximal ends of the void.43. A method for preparing a sacroiliac joint for stabilization, thesacroiliac joint defined between a sacrum and an ilium, the methodcomprising: approaching a posterior aspect of the sacroiliac joint witha defect-creating tool assembly comprising a first cutting tool and afirst cutting guide, the first cutting guide comprising a first cuttingguide path configured to guide the first cutting tool along a firsttrajectory; creating a defect in the sacrum and the ilium by deliveringthe first cutting tool into at least one of the sacrum, the ilium, andsacroiliac joint via guidance by the first cutting guide path of thefirst cutting guide, respectively, the defect having a shape defined bya cross-sectional shape in a plane generally perpendicular to a jointplane of the sacroiliac joint; and delivering an implant into thesacroiliac joint, the implant comprising a body extending a lengthbetween a proximal end and a distal end, and having a generallyrectangular volume including a sacral side opposite an iliac side, a topside opposite and bottom side, an opening extending between the top andbottom sides, and first and second passages extending through theproximal end, wherein a location of the first passage is positionedadjacent the sacrum and a location of the second passage is positionedadjacent the ilium, and a first portion of an exterior surfaceconfigured to generally match the cross-sectional shape of the defectcreated by the defect-creating tool assembly; and delivering a firstelongate member into engagement with the sacrum while supported by thefirst passage, and delivering a second elongate member into engagementwith the ilium while supported by the second passage.